Webcast of SpaceX rocket engine test

The Falcon craft being tested will send a Dragon capsule to the ISS.

SpaceX will fire all nine engines of the Falcon 9 rocket currently on the pad at Cape Canaveral, Florida today as part of a full-on dress rehearsal for the second launch of its Dragon spacecraft. Dragon will attempt a rendezvous with the International Space Station after a series of maneuvers intended to prove the craft's orbital maneuvering and navigation system.

If the maneuvers and berthing all go as planned, astronauts will open up the spacecraft and unload the supplies, then reload it with items for Dragon to return to the Earth. Dragon is the first commercial spacecraft to attempt a rendezvous with the International Space Station, and the first cargo spacecraft to be reusable. The renewed availability of the ability to send cargo back down to Earth after the retirement of the shuttle will make a huge difference in Station operations.

If all goes well this afternoon, SpaceX has set a new date of May 7 for the launch. This carries an enormous political payload in an election year because of the Obama administration's attempt to jump-start a commercial orbital space launch industry in the face of heavy Republican opposition. This afternoon's webcast will begin at 2:30pm Eastern Time, with the actually test firing scheduled for 3:00pm. You can watch the webcast at the SpaceX website.

HOLD at T-47s with transients on Dragon startup. They should be able to recycle from T-13m and try again, but they won't get a second chance on launch day (instantaneous launch window). This is why it's such a nifty feature that Falcon 9 can do a static fire test on the launch pad. Most launch vehicles can't do this.

On launch day if the instantaneous window is missed how long is the wait until the next window?

Quote:

When visualizing plane window scenarios, it’s important to remember that Earth rotates at 1,035 mph, but an object’s orbit is fixed in space. That means that the orbital path of the ISS passes over a different part of Earth on each 90-minute, 17,000-mph orbit—the station’s “ground track” is always sliding to the west. The ground track of the ISS may cross near Kennedy Space Center on one orbit, but when it comes back around 90 minutes later, Earth will have rotated and the orbit will cross at a point about 1,000 miles due west. The result: There is only one plane window per day for a rendezvous mission, because it takes about 24 hours (Earth’s circumference is approximately 25,000 miles, divided by a rotation rate of 1,035 mph) for the target orbit to return.

On launch day if the instantaneous window is missed how long is the wait until the next window?

Launch opportunities every three days, subject to range availability and ISS conflicts. The range shouldn't be a problem, but there's a Soyuz mission to the ISS launching May 14/15 with an associated crew rotation, and that might prevent a launch on May 10, 13, and/or 16.

Dragon is man-rated for berthing to the ISS. Note that Dragon's pressure vessel and pressurization system impact the rest of the ISS while the spacecraft is berthed, and the ISS crew will be doing cargo transfers inside Dragon, so it has to be man-rated for that stuff.

It's just not man-rated for launching people until the SuperDraco launch escape system is integrated, flight-tested, and validated. There some other small things, but mainly it's the escape system.

Dragon is man-rated for berthing to the ISS. Note that Dragon's pressure vessel and pressurization system impact the rest of the ISS while the spacecraft is berthed, and the ISS crew will be doing cargo transfers inside Dragon, so it has to be man-rated for that stuff.

It's just not man-rated for launching people until the SuperDraco launch escape system is integrated, flight-tested, and validated. There some other small things, but mainly it's the escape system.

Cool -- thanks for clearing this up for a space-geek who's not that up on regulations!